WASHINGTON — Once again, the ability to write a personal check to cover campaign expenses has proved to be insufficient to get elected, as 80% of self-funded candidates went home as losers.

Republican Linda McMahon, the former CEO of what was World Wrestling Entertainment, spent nearly $43 million of her own money this year running a second time for a U.S. Senate seat in Connecticut, according to the Associated Press. She spent roughly $66 per vote, according to USA TODAY calculations, as she lost to Democratic Rep. Chris Murphy.

McMahon was the biggest spender — or some would say, biggest loser — among the self-funding candidates for Congress this year. Of the 49 candidates for Congress who spent significant sums of their own money to run for the U.S. House and U.S. Senate, only nine won their races, according to the non-partisan Center for Responsive Politics.

The track record of self-funding candidates has been consistent, campaign-finance experts say.

"There is no guarantee of a win, but a lack of money is a guarantee of losing," said Meredith McGehee, policy director of the Campaign Legal Center. "It's never been about who spends the most money. You just have to have enough money. There's not been a scientific formula for the definition of 'enough.' "

Jennifer Steen, an assistant professor of political science at Arizona State University, said self-funding candidates often have trouble translating their financial success into the political arena.

While there are successful self-funding political candidates who already have meaty résumés — such as New York City Mayor Michael Bloomberg, who made a fortune in the financial news service that bears his surname and has spent over $250 million in three campaigns — there are more like Meg Whitman who fall short. The former e-Bay chief, now head of Hewlett-Packard, spent about $142 million of her own money in her unsuccessful 2010 bid for California governor.

"Many of them have impressive credentials in life, but that doesn't really translate into a compelling story to tell voters," said Steen, author of a book on self-financing candidates for Congress.

Democrat Suzan DelBene is a candidate who did get voters on her side. The former Microsoft executive and founder of drugstore.com spent more than $2.8 million on her successful House race in Washington. DelBene was sworn in last week to complete the remaining term of Democrat Jay Inslee, who resigned to run for governor, and will also be his successor in the 113th Congress.

Self-funding candidates say they invest in their own races to show that they aren't beholden to special interests. McMahon bristled in a post-election interview with Bloomberg News at a suggestion that she tried to buy the campaign.

"What would be my personal gain? I'm not looking for a new career," McMahon said in the interview. "I've had a wonderful career. I was hoping to bring a different voice and perspective and use my skills that have been honed as a CEO bringing people together. ...I wasn't looking for a hobby. If I were looking for a hobby, it wouldn't be the United States Senate."